After the resilience the agriculture sector has been showing in the face of economic uncertainty, I am not really surprised by PotashCorp's (NYSE: POT) awesome third-quarter numbers. Strong crop prices were bound to fuel demand for nutrients -- a factor that has played out very well in Potash's favor.

Market conditions suggest a strong future for the company. Read on to learn what they are.

Surging margins
Potash revenue more than doubled to $700 million from last year, as shipments and prices went up. Emerging markets contributed the most to sales. Peers' numbers are just as good, with China Green Agriculture's (NYSE: CGA) fourth-quarter revenues up more than three times.

Prices of all three nutrients PotashCorp deals in -- potash, phosphate, and nitrogen -- went up in the third quarter, driving up the company's top line by an astounding 47% from the year-ago period to $2.3 billion.

Higher nutrient prices were also the primary drivers behind peer CVR Partners' (NYSE: UAN) solid 66% jump in its third-quarter revenue. Mosaic's (NYSE: MOS) first-quarter revenue also jumped an amazing 41% from the year-ago quarter to $3.1 billion as prices went up.

Potash's bottom line surged to $826 million from $343 million a year ago on the back of the solid top-line growth.

Crop prices rise, PotashCorp gains
Skyrocketing crop prices have pushed up farming activity globally, thereby raising demand for fertilizers and nutrients. Among crops, corn, which requires a lot of nutrients, touched its highest price levels this year. And the market for corn is getting tighter, with the 2011 corn yield expected to be low.

The fact that China, which exported corn until a couple of years back, has recently made its biggest purchase of 900,000 metric tons of American corn, indicates the soaring consumption of corn. And this will mean higher demand for Potash's nutrients.

The market for most nutrients such as potash is getting tight, and PotashCorp is making efforts to capitalize on this opportunity.

The cartel benefit
PotashCorp is undertaking heavy expansion. The biggest projects, amounting to billions of dollars of investment, are its potash mine expansions in Saskatchewan and New Brunswick, Canada. With global population and food spending soaring, most potash producers are expanding. Mosaic, for instance, has a 5-million-ton potash expansion program under way.

Being the world's largest fertilizer producer definitely has its advantages. All potash exports out of Saskatchewan are controlled by a three-member legal cartel, Canpotex, composed of Potash, Mosaic, and Agrium (NYSE: AGU), and Potash owns 54% of it.

With India agreeing to import potash at the currently prevailing high prices -- something the country was not willing to do for months -- the three big potash players will gain tremendously from the committed exports. Moreover, shipments from Canpotex will be at much higher rates in 2012. These commitments should mean solid gains for Potash.

The Foolish bottom line
PotashCorp expects record potash industry shipments in 2012, and the tight market conditions coupled with high prices should pave the way for robust forthcoming quarters.

I feel there's a lot of promise in the world's largest fertilizer maker, and if you do not want to be left out of PotashCorp's progress, news, and analysis, make sure you add it to your stock watchlist. It's a free, personalized stock-tracking service from The Motley Fool to keep you updated on all your favorite companies.